This pack­age pro­vides an en­vi­ron­ment for coloured and framed text
boxes with a head­ing line. Op­tion­ally, such a box may be split in
an up­per and a lower part; thus the pack­age may be used for the
set­ting of LaTeX ex­am­ples where one part of the box dis­plays the
source code and the other part shows the out­put. Another com­mon
use case is the set­ting of the­o­rems. The pack­age sup­ports sav­ing
and reuse of source code and text parts.